Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! See news and announcements

GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

19565 results found.

  1. GRB050603, submillimetre observations
  2. GRB 050603: Swift XRT Position
  3. GRB050603: Radio Detection
  4. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  5. GRB 050603: INTEGRAL shows it is not a short GRB
  6. Swift/BAT Detection of GRB050603
  7. GRB 050525a, infrared observations
  8. GRB050528: updated Liverpool Telescope limits
  9. Swift-BAT GRB 050528: a soft burst
  10. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  11. Possible GRB050528: no candidate from Liverpool Telescope
  12. GRB050525a: Radio Observations
  13. GRB 050509b: refined XRT/Chandra afterglow position analysis
  14. GRB 050525: RTT150, Optical observations
  15. GRB 050525a: SARA Observations
  16. GRB 050525B: Swift-BAT observations
  17. GRB 050525: MITSuME Optical Observation in VRI
  18. GRB050525A,optical observation
  19. GRB050525: Super-LOTIS observations
  20. GRB050306: optical afterglow not confirmed
  21. GRB 050525: BART optical observation
  22. GRB 050525A: BOOTES simultaneous optical observations
  23. GRB050525: Optical observations
  24. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  25. GRB 050525: TAROT observations of the early afterglow
  26. INTEGRAL detection of GRB 050525
  27. GRB 050525, infrared observations
  28. GRB 050525: Optical observation
  29. GRB 050525: observatons of the optical afterglow
  30. GRB050525: ROTSE-III Refined Analysis
  31. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  32. XRF050522: Radio Observations
  33. Swift/UVOT observation of XRF 050522
  34. GRB 050509A: Further I-band imaging
  35. GRB050522,optical observation
  36. GRB050520,optical observation
  37. XRF 050522: Continued NIR P200 Monitoring
  38. RBO Observations of GRB050522
  39. Recent GRB BVRcIc field photometry
  40. GRB050520: Radio Observations
  41. XRF 050522: Swift XRT observation
  42. XRF050522, BVRcIc field photometry
  43. XRF050522: Optical Observations
  44. XRF050522: Near-infrared Observations
  45. GRB 050520: VLT/ULTRACAM observations
  46. Swift UVOT Observations of GRB 050520
  47. XRF050509c: Radio Observations
  48. RBO Observations of GRB050520
  49. GRB 050520: P200 Observations
  50. GRB050520: Liverpool Telescope follow-up
  51. RBO Observations of GRB050520
  52. GRB 050520: TAROT optical limit
  53. GRB 050520: VLT/ULTRACAM observations
  54. GRB050502b: Early Observation
  55. GRB050509b, Bok telescope B-band imaging
  56. GRB050509b, SDSS pre-burst observations
  57. GRB 050509b: Keck/Chandra Cross-Correlation
  58. GRB 050509b: Keck/Chandra Cross-Correlation
  59. Chandra observation of GRB 050509b
  60. GRB 050509b Milagro GeV/TeV Observations
  61. GRB050509B: Optical observations at the Very Large Telescope
  62. GRB 050509b: No Optical Variability in XRT Error Circle
  63. GRB 050509c: ROTSE-III Optical Limits
  64. GRB 050505, early TAROT observation
  65. GRB050509c: REM NIR and Optical observations
  66. GRB 050505: SARA Observations
  67. GRB 050509B: Swift/XRT refined analysis
  68. GRB 050509A: Optical observations
  69. GRB050509b: Radio Observations
  70. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  71. Swift Detection of GRB050509b: A short duration burst
  72. Swift Detection of the Burst GRB050509
  73. GRB 050505, simultaneous optical observation
  74. GRB050505: AAVSO observations
  75. GRB050416A : 1 GHz limit from GMRT
  76. GRB050505: Optical Afterglow Candidate
  77. GRB 050416b:Swift XRT afterglow upper limits
  78. GRB 050416b:Swift XRT afterglow upper limits
  79. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  80. GRB050502b: Afterglow Confirmation
  81. GRB050502: P200 Observations (Correction)
  82. GRB050502: P200 Observations
  83. Swift UVOT observation of GRB 050504
  84. GRB050504: P60 Observations
  85. GRB 050504: A long GRB detected with INTEGRAL
  86. GRB (?) 050504: IR Observations, Intriguing Source
  87. GRB 050502b, Optical observations
  88. GRB050502a: P60 Observations (Correction)
  89. GRB050502a: P60 Observations
  90. GRB050502B Swift-BAT refined analysis
  91. Swift Detection of the Bright Burst GRB050502b
  92. GRB 050502: ROTSE-III Detection of Possible Counterpart
  93. Swift/BAT possible detection of a weak burst GRB050430
  94. GRB050416a: Radio Detection
  95. Swift Detection of GRB 050422
  96. GRB 050421: SLOTIS observations
  97. GRB 050421: Further Analysis of IR imaging
  98. GRB050421: Radio Observations
  99. GRB050421: Radio Observations
  100. GRB 050421: IR Observations

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov